Using my system I see a multitude of options to record and import sound but it is very confusing what does what.

In the last test I wanted to use the sound of one (main) camera as master sound, while the others are muted.
In this case I use the embedded sound in the HD-SDI stream.
However, I could not find a solution to this, when switching from camera to another camera vMix also switched to the audio stream of that camera.

Because of all the different camera positions the varying sound can then only be used as guide-track.
Ideally, I would connect one camera to the output of the mixing desk via its audio XLR inputs (Sony EX-3 in this case) and mute all other cameras, keeping only the one audio stream live all the time while switching.

who can get me on the right track?

Thanks,

Rob